This invention pertains to an anti-theft device, in particular for skis. It comprises a cable, in particular with one end of the cable securely connected to a cable drum, and a locking mechanism that has at least one clamping member and one lock. The purpose of the clamping member is to secure the cable that is inserted into the locking mechanism. It cooperates with the lock in such a way that the clamping member releases the cable when the lock is opened and when the lock is closed, it secures it against removal in the direction opposite to the direction of insertion.
A wide variety of designs for these types of anti-theft devices are already well known (see for example WO 95/31625) that are characterized by different advantages, each of which also has its corresponding disadvantages, however. They are used especially for the fastening of skis, luggage, bicycles and similar easily stolen objects. For example, a well known cable lock of the type mentioned above has a tilting clamping member that presses against the cable at an angle such that the desired clamp effect is obtained only when the cable is inserted in a prescribed direction. The other end of the clamping member opposite the cable acts directly on the lock so that the forces transferred to the clamping member when someone tries to remove the cable is directly transferred onto the lock. This can lead to warpage in the lock area and even to loss of function of the lock.
With this in mind, the object of this invention is to improve an anti-theft device of the type mentioned above to the extent that the disadvantages described are prevented or that a simple and more easily operated anti-theft device results overall.
This object is met through the invention in that the clamping member is mounted in the locking mechanism such that it rotates and shifts, and cooperates with the lock by means of a pivoting lever, and that the lock is coupled to the clamping member via the pivoting lever with respect to the rotating motion of the clamping member. Whereas in the described state of the art, the clamping member merely tilts between an open and a closed position and is acted upon by both the cable and by the lock in the closed position, the anti-theft device according to the invention has a functional separation of the two. This is accomplished in that the lock acts on the pivoting lever, which in turn is connected to the clamping member such that when an attempt is made to pull out the cable from the locking mechanism, the clamping member only acts upon the pivoting lever in the direction of the pivoting lever axis. This prevents the force from being translated into a pivoting motion that would transfer the force onto the lock because of the lack of any transverse components. In this way, it can be ensured that the function of the lock is not compromised by manipulation at the cable.
By mounting the clamping member in a rotatable fashion, and because its rotation does not cause the pivoting lever to rotate as well, the locking mechanism functions in both insertion directions. Thus, the cable can be inserted in the locking mechanism from either side. It can also be secured with the help of the clamping member, which further improves the ease of use of the anti-theft device. This two-way utility is supported further in that the clamping member includes a rounded off cam that has no edges directed at the cable when it is inserted.
It is particularly advantageous for the locking mechanism to have two rotatable and shiftable clamping members mounted within it, used to fasten two cable sections. These members cooperate with the lock through separate pivoting levers. This enables the locking mechanism to form two cable loops in the cable, making movable objects more secure against theft. This is because the first loop can be laid around the object to be secured and thus be stretched tight enough that the object cannot be pulled out of the loop, while the second loop can be laid around a stationary componentxe2x80x94such as a ski stand, a sign or lamp post or something similar. If someone were to try and to wrap the object to be secured as well as the stationary component inside a single loop, the risk would be very high that there would possibly still be enough play to remove the objects to be secured from the loop. Of course, this especially applies to skis, which have no openings that the cable can pass through.
In this regard, it is also recommendable that the pivoting lever, or each pivoting lever, cooperate with the lock by means of a positioning element connected to the lock, mounted in the locking mechanism and which is rotatable. This further improves the decoupling of force between the clamping member and the lock. It would be advantageous to combine this positioning element with both pivoting levers, in particular on opposite sides of the positioning element so that both clamping members can be secured and blocked using a single closing motion.
With respect to the pivoting lever, it rotates within the locking mechanism between a first rotation position in which the positioning element acts upon a first side of the pivoting lever, keeping it from rotation, and a second rotating position in which the positioning element acts upon a second side of the pivoting lever, keeping it from rotating. This enables the decoupling of force mentioned above to be ensured in that the positioning element contacts the pivoting lever perpendicular to the direction that the force can be transferred from the clamping member to the pivoting lever when someone tries to remove the cable, especially in the closed lock position. In this way, the positioning element can remain absolutely free of the force components generated.
To rotate the positioning element, a key inserted into the lock is turned. This key can be removed from the lock in the closed position in order to prevent unwanted operation of the lock. The positioning element in the first rotational position of the pivoting lever corresponds to the closed position of the lock, whereas the second rotational position corresponds to the opened position of the lock.
With respect to the clamping member, it is held in a guide provided in the locking mechanism and can be rotated using a hinge pin or a similar attachment, wherein the guide runs approximately perpendicular with respect to the cable when it is inserted in the locking mechanism and toward it so that the clamping member can be shifted, by means of the hinge pin and guide, between a position away from the cable and a position pressing against the cable, perpendicular to the direction in which the cable extends. This allows the clamping member to be lifted off in the open position of the lock. To this end, the guide is designed as a slot that holds the hinge pin located in the housing of the locking mechanism.
Moreover, it is recommended that the clamping member, i.e. each clamping member, be tensioned toward the inserted cable, in particular through the force of a spring, which keeps the clamping member in its initial, non-tilted position.
With respect to the cooperation between clamping member and pivoting lever, it is recommended that these two components be connected using a rotatably fastened coupling element, wherein, again, the connection of clamping member and coupling element is done through the hinge pin mentioned above. Also, the pivot lever and the coupling element together form a pivoting joint and can be rotated in opposite directions using the common joint axis. The joint axis is located near the first side of the pivoting lever.
Moreover, it is recommended that the locking mechanism have at least one through passage to insert and pull through the cable, and that the clamping member act upon the inserted cable near the through passage. The through passage is formed by a channel that is sized approximately to fit the shape of the cable, wherein the clamping member fixes the cable against the walls of the channel without play when the lock is shut and the cable is inserted. In order to make removal of the cable more difficult or to prevent it, the channel should be given a profile that acts upon the cable, in particular with a right-handed and left-handed thread.
Also, the fastening of the cable is improved even more if the clamping member is forwarded from a cam that is provided with a profile where it acts upon the cable, in particular with a tooth profile.
An important advantage of the anti-theft device of the type mentioned above is accomplished in that the cable drum has a housing to keep the cable in its interior, that the lateral length of the housing interior is approximately equal to the cable diameter so that the safekeeping of the cable is accomplished by a single-row spiral in the interior. Neighboring cable windings lie against one another in the radial direction. The fact that, for a long time, previous cable locks were unwieldy because the cable had become entangled inside the housing interior is the reason for this design feature. Because of the spring force associated with the cable, every cable winding tends to press against the outer walls. If the width of the housing interior is such that a number of cable windings can be located next to one another in the lateral direction, this entanglement and blocking of the cable in the housing interior is inevitable. This type of entanglement is thus prevented by means of the invention in that the cable is wound in only a single-row.
It is also particularly advantageous in this regard if the housing has not only one, but a number of openings located at least in the radial direction at the outer walls of the housing. The cable can be unwound through them from the interior of the housing. Through this multitude of openings, which should be dimensioned sufficiently large, the end of the cable can be placed in the housing without there being a problem in retrieving it due to the end of the cable not being near the opening in the housing, such that the end of the cable becomes irretrievably lost in the housing. In this way, the end of the cable can be moved in a simple manner to the next opening by moving the housing relative to the end of the cable, whereupon the cable end springs out through the opening by means of a reacting spring force. The cable drum is fastened to the locking mechanism and the housing of the cable drum can be rotated with respect to the locking mechanism so that the rotation mentioned can be made in a simple manner by a short relative motion between the housing and the locking mechanism.
Finally, it is recommended that the lock extend in the direction of the rotating axis and to be rotationally fixed to the locking mechanism, and that the direction of insertion of the key correspond to the rotating axis, i.e. be parallel to it. In this way, the lock constitutes the rotating joint for the housing simultaneously, which results in an optimization with respect to assembly. The results in a very easy-to-use cable lock with a single-row spiral cable winding, which allows the end of the cable to be stored in the wound state in the housing. The exterior dimension of the cable lock then can be further reduced.